Using AWS Systems Manager to Upgrade WordPress

devops

After years of manually upgrading my self-hosted WordPress installation, I decided it was finally time to apply some devops principles (namely automation) to this process.

This site runs on an EC2 instance on AWS, so I decided to use AWS Systems Manager (aka SSM). I started out by creating the following Command Document (which happens to be in YAML format because JSON is ugly):

The Command Document executes the bash commands in the runCommand section. It downloads the latest version of WordPress, stops Apache, unzips the files, restarts Apache, and then cleans up.

SSM uses an agent to carry out the bash commands. My instance runs Amazon Linux which comes with the agent preinstalled, so I didn’t need to install it.

Systems Manager can execute the Command Document at regular intervals to keep up with the typical WordPress release schedule of every 1-2 months. I can also trigger it manually if there’s a security or bugfix release I need.

To avoid catastrophe, I have the Amazon Data Lifecycle Manager for EBS Snapshots take daily snapshots of the instance, just in case something goes terribly wrong with an upgrade.

I know what you’re thinking. “Why use Visual Studio Code instead of the PowerShell ISE?” Well, if you’re using Mac OS or Linux, you don’t have the option to use the PowerShell ISE natively. And that’s a problem if you want to take advantage of the cross-platform capabilities of PowerShell Core. In this article, I’ll show you how to use Visual Studio Code (free!) to perform the key functions of the PowerShell ISE, namely:

Simultaneously view code and execute it in the PoSh terminal

Execute code on a selection or line-by-line basis (F8)

Syntaxhighlighting (for people who are easily bored like me)

Installing Visual Studio Code

The best way to install most things is with a package manager. This would be something like apt-get or yum for Linux distros, homebrew for Mac OS, and Chocolatey for Windows. Or you could go old school and download it here.

Installing the PowerShell Extension

Go to the Extensions button (looks like a busted up square) or View > Extensions.

If the PowerShell extension doesn’t show up under the bombastic “RECOMMENDED” heading, just search for it in the “Search Extensions” field. Then install it.

Integrating the PowerShell Terminal

Open up a PowerShell script of your choice. Then in the menu, go to View > Integrated Terminal. You should see the following.

If you don’t see the PS prompt Make sure you select “TERMINAL” and “PowerShell Integrated” from the drop-down menu.

Running Only Selected Code

In the PowerShell ISE, you can select a block of text and hit F8, and the ISE runs only that code. Or you can position your cursor at the end of a line and hit F8, and the ISE runs only the code on that line. Next we’ll enable the exact same behavior in Visual Studio Code.

Go To File > Preferences > Keyboard Shortcut

In the text entry field at the top, type “runsel”. You should see two items:

“Run Selection” with a keybinding to F8

“Run Selected Text In Active Terminal” with no keybinding

This is not what we want because it will not run the selected text in the PowerShell terminal. It will run the selection in the “OUTPUT” section, but not in the terminal. Obviously, that’s not the normal behavior of the PowerShell ISE. Let’s fix it.

Testing It Out

Go back to your code and select a block of code. Hit F8 and watch the magic!

That’s what I’m talking about!

But… as of this writing, there’s an issue with this that’s being tracked on the vscode-powershell GitHub repo, and it’s this: multi-line input in the integrated console doesn’t work. That means you can’t select a function block, hit F8, and have it work. It will throw ugly errors in your face.

Forget using scripts and group policies to configure a new Windows Server machine. Using Chocolatey and Puppet, you can do it faster & easier than ever (and it’s more fun too). This is especially true if you’re using a Server Core installation and don’t have a GUI to help you along. Oh, and if you don’t know Puppet, you really should watch my course Puppet Fundamentals for System Administrators on Pluralsight 🙂